1. Field of Invention
This invention relates to a priority controlled network, wherein a plurality of sensor terminals and at least one display terminal are connected to a network and priority of data from the plurality of sensor terminals to the network are selectively displayed on the at least one display terminal.
2. Discussion of the Prior Art
In a conventional surveillance system using a plurality of TV cameras, at least one display unit, and a network connecting the cameras and display unit, the problem of limited capacity of the network can be troublesome. For example, an operator might not recognize an emergency situation since he cannot simultaneously view all of the iamge data from all the cameras. Also, the total amount of data can readily exceed the capacity of the network so that priority of data is difficult to maintain. Improvement is needed to enable more efficient and reliable use of networks and display of data based on a predetermined priority value.
A conventional network is known which uses a plurality of sensor terminals, such as TV cameras, connected to a network. Each sensor terminal determines the priority of its data. Where the network has a certain capacity, for example, 10 image data, and the number of sensors exceeds the capacity, it has been suggested that the sensor terminal having the least valuable priority, such as the 10th, stop transmitting if it has less than the 10th value priority. Although, such suggested system may solve the immediate problem, there is the disadvantage that the number of sensors at each terminal is fixed, and hence, flexibility of design is reduced.
Accordingly, an object of the invention is to overcome the aforementioned and other deficiencies, disadvantages and problems of the prior art.
Another object is to provide a priority controlled network, such as used for visual surveillance systems, wherein a selective priority method enables expansion of the priority capacity of the network, and increase flexibility of design.
The foregoing and other objects are attained by the invention, which encompasses a priority controlled network, wherein one or more parameters used at a sensor terminal is supplied to determine priority value and are varied so that priority data are determined by the varied parameters and the sensor terminals having the desired priority values are selected in a network having a capacity of the highest priority value. For example, a network having a capacity of 10 sensors can have more than 10 sensors when the priority values are determined for 10 values of the more than 10 sensors.
The foregoing procedure is applied to a plurality of sensor terminals, at least one display terminal, and control unit interconnected to a network, wherein the control unit supplies the parameters, such as priority calculation algorithm and priority calculation equations, and priority value determination is made by a priority calculation unit in the sensor terminals.